diff options
| -rw-r--r-- | include/linux/kobj_completion.h | 18 | ||||
| -rw-r--r-- | lib/kobject.c | 50 |
2 files changed, 68 insertions, 0 deletions
diff --git a/include/linux/kobj_completion.h b/include/linux/kobj_completion.h new file mode 100644 index 000000000000..a428f6436063 --- /dev/null +++ b/include/linux/kobj_completion.h @@ -0,0 +1,18 @@ +#ifndef _KOBJ_COMPLETION_H_ +#define _KOBJ_COMPLETION_H_ + +#include <linux/kobject.h> +#include <linux/completion.h> + +struct kobj_completion { + struct kobject kc_kobj; + struct completion kc_unregister; +}; + +#define kobj_to_kobj_completion(kobj) \ + container_of(kobj, struct kobj_completion, kc_kobj) + +void kobj_completion_init(struct kobj_completion *kc, struct kobj_type *ktype); +void kobj_completion_release(struct kobject *kobj); +void kobj_completion_del_and_wait(struct kobj_completion *kc); +#endif /* _KOBJ_COMPLETION_H_ */ diff --git a/lib/kobject.c b/lib/kobject.c index e769ee3c2fb9..a5a9b13b0648 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -13,6 +13,7 @@ */ #include <linux/kobject.h> +#include <linux/kobj_completion.h> #include <linux/string.h> #include <linux/export.h> #include <linux/stat.h> @@ -750,6 +751,55 @@ const struct sysfs_ops kobj_sysfs_ops = { }; /** + * kobj_completion_init - initialize a kobj_completion object. + * @kc: kobj_completion + * @ktype: type of kobject to initialize + * + * kobj_completion structures can be embedded within structures with different + * lifetime rules. During the release of the enclosing object, we can + * wait on the release of the kobject so that we don't free it while it's + * still busy. + */ +void kobj_completion_init(struct kobj_completion *kc, struct kobj_type *ktype) +{ + init_completion(&kc->kc_unregister); + kobject_init(&kc->kc_kobj, ktype); +} +EXPORT_SYMBOL_GPL(kobj_completion_init); + +/** + * kobj_completion_release - release a kobj_completion object + * @kobj: kobject embedded in kobj_completion + * + * Used with kobject_release to notify waiters that the kobject has been + * released. + */ +void kobj_completion_release(struct kobject *kobj) +{ + struct kobj_completion *kc = kobj_to_kobj_completion(kobj); + complete(&kc->kc_unregister); +} +EXPORT_SYMBOL_GPL(kobj_completion_release); + +/** + * kobj_completion_del_and_wait - release the kobject and wait for it + * @kc: kobj_completion object to release + * + * Delete the kobject from sysfs and drop the reference count. Then wait + * until any other outstanding references are also dropped. This routine + * is only necessary once other references may have been taken on the + * kobject. Typically this happens when the kobject has been published + * to sysfs via kobject_add. + */ +void kobj_completion_del_and_wait(struct kobj_completion *kc) +{ + kobject_del(&kc->kc_kobj); + kobject_put(&kc->kc_kobj); + wait_for_completion(&kc->kc_unregister); +} +EXPORT_SYMBOL_GPL(kobj_completion_del_and_wait); + +/** * kset_register - initialize and add a kset. * @k: kset. */ |
